This application relates to a sealed rotator shaft for use in borescopic inspection.
Gas turbine engines are known, and typically include a compressor section compressing air and delivering the compressed air into a combustion section. The compressed air is mixed with fuel and combusted, and products of this combustion pass downstream over turbine rotors. The turbine rotors are driven to rotate, and in turn rotate rotors in the compressor section.
One method of inspecting a gas turbine engine is called borescopic inspection. With borescopic inspection, probes are inserted through holes in the sections in a gas turbine engine. For certain aspects of the inspection, the turbine and compressor rotors must be rotated. Thus, it is known to have a rotator shaft associated with a gas turbine engine.
In the existing art, the rotator shaft has typically been part of an accessory drive gearbox. A sealed cover is aligned with an accessory shaft. The accessory shaft is connected through a gear train back to a main engine shaft connecting the turbine rotors and the compressor rotors. When borescopic inspection is to occur, the cover is removed, and a technician will insert a tool that engages the accessory shaft to rotate the turbine rotors. In the past, inspectors have sometimes neglected to replace the cover after the inspection is complete. This is undesirable, as the oil may drain out of an accessory gear case once the engine is returned to operation.